cleaning distrib trigger points
 

I've removed the distributor on my 1975 450 SL because about every 6 months oil leaks past the bearings into the upper part of the distributor. I 've removed the triger points and would like advice on what to use to clean them with. Is there a simple spray-on that will do the job or a solution they can be dipped in? Any suggestions are gratefully accepted.
Thanks in advance.